Two subway trains have collided during a new signal system test in Hong Kong, halting services and threatening travel disruption for millions of commuters.The incident occurred between the Central and Admiralty stations before the service was open to the public early on Monday morning.

According to reports the trains had no passengers on board, however both drivers were taken to hospital.

Network operator Mass Transit Railway (MTR) said sections of the Tsuen Wan Line had been suspended and urged commuters to avoid the route affected and to use other forms of transport if possible. Investigation into the incident is under way.

Sources said that further disruption was caused later, when a woman fell on to the tracks at Kowloon Tong station, causing a temporary suspension of service in that area.